android 加载图片

.Android在加载大背景图或者大图片时，经常导致内存溢出（Out of Memory Error）

可们可能跟据imageView的宽高来对图片进行压缩，关效的解决（Out of Memory Error）

直接上代码：

xml

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"    xmlns:tools="http://schemas.android.com/tools"    android:layout_width="match_parent"    android:layout_height="match_parent"    android:paddingBottom="@dimen/activity_vertical_margin"    android:paddingLeft="@dimen/activity_horizontal_margin"    android:paddingRight="@dimen/activity_horizontal_margin"    android:paddingTop="@dimen/activity_vertical_margin"    tools:context=".MainActivity" >          <ImageView       android:src="@drawable/ic_launcher"       android:id="@+id/image"       android:layout_height="fill_parent"       android:layout_width="fill_parent"       /> <Button        android:onClick="onClick"        android:layout_width="wrap_content"        android:layout_height="wrap_content"        android:text="@string/hello_world" /></RelativeLayout>

java

    ImageView image;    @Override    protected void onCreate(Bundle savedInstanceState) {        super.onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        image=(ImageView) findViewById(R.id.image);    }    @Override    public boolean onCreateOptionsMenu(Menu menu) {        // Inflate the menu; this adds items to the action bar if it is present.        getMenuInflater().inflate(R.menu.main, menu);        return true;    }        public void onClick(View view){    //解析图片时需要使用到的参数都封装在这个对象里了    Options opt = new Options();    //不为像素申请内存，只获取图片宽高    opt.inJustDecodeBounds = true;    BitmapFactory.decodeResource(getResources(), R.drawable.dog, opt);    //拿到图片宽高    int imageWidth = opt.outWidth;    int imageHeight = opt.outHeight;        Display dp = getWindowManager().getDefaultDisplay();    //拿到屏幕宽高int screenWidth = dp.getWidth();    int screenHeight = dp.getHeight();        //计算缩放比例    int scale = 1;    int scaleWidth = imageWidth / screenWidth;    int scaleHeight = imageHeight / screenHeight;            int max=Math.max(scaleWidth, scaleHeight);        if (max>scale) {    scale=max;}        //设置缩放比例    opt.inSampleSize = scale;    opt.inJustDecodeBounds = false;    Bitmap bitmap=BitmapFactory.decodeResource(getResources(), R.drawable.dog, opt);    image.setImageBitmap(bitmap);    }    }

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